Cautions:
1. Take heed that you choke not those convictions that at present do break your hearts.
2. Shun vain company.
3. Take heed of idle talk.
4. Beware of the least motion to sin.
5. Take heed of evil examples among the godly.
6. Take heed of unbelief, or atheistical thoughts.
Directions:
1. Labour after a deep knowledge of God to keep it warm upon thy heart.
(i) Knowledge of his piercing eye, that it runneth to and fro through the earth, beholding in every place the evil and the good; that his eyes behold, and his eyelids try the children of men (Prov 15:3).
(ii) The knowledge of his power, that he is able to turn and dissolve heaven and earth into dust and ashes; and that they are in his hand but as a scroll or vesture (Heb 1:11, 12).
(iii) The knowledge of his justice, that the rebukes of it are as devouring fire (Heb 12:19).
(iv) The knowledge of his faithfulness, in fulfilling promises to them to whom they are made, and of his threatenings on the impenitent (Matt 5:18, 24:35; Mark 13:31).
2. Labour to get and keep a deep sense of sin in its evil nature.
3. Consider of death, both as to the certainty of thy dying, and uncertainty of the time when.
4. Consider also of the certainty and terribleness of the day of judgment, when Christ shall sit upon his great white throne.
5. Consider, Christ Jesus did use no means to harden his heart against doing and suffering those sorrows which were necessary for the redemption of thy soul.
[These are the main headings from The Acceptable Sacrifice, Chapter 7, 'Keeping the heart tender' and can be read in full here.]